New Nomenclature
Today, the industry prefers the new TO-226 nomenclature for the TO-92 three-leaded enclosure.
There are three TO-206 variants: TO-206AA with three straight leads; TO-206AB with the lead 2 formed to create a triangular pattern between the leads and the TO-206AC with the lead 2 omitted. (the latter is in fact a diode package and is mainly used for Varactor tuning diodes and shunt voltage references).
Read more about this topic: TO-92